May 22: ORD

Today is May 22nd. It's the 142nd day of the year. 223 days remain. It's week 21 of the year.

Unless noted, the following data is based upon observations collected by the National Weather Service, Chicago, at O'Hare International Airport (ORD) between November 1978 and last year. ORD has been the official site of record for Chicago since Thursday, January 17, 1980.

According to the National Climatic Data Center (NCDC), the normal high is 72 and the normal low is 50. I've calculated the 32-year averages at 72 and 50.

On the warm side, in 1991 the high was 84 with a low of 67. Three years later, in 1994, the high was 89 with a low of 58, a 31 degree spread. Two years earlier, in 1992, the high was 83 with a low of 63. Another warm high was 87 in 2007. The record high of 94 was set back in 1925. The record warmest low of 75 was set in 1977. 23 of the last 32 highs (72%) highs were in the: 60s (12) and 70s (11). Seven highs (22%) were in the warmer 80s. Two highs were in the cool 50s. The highs over the past seven years were in the 60s, 70s and 80s except for 59 in 2008.

In looking back through the years to the first May at O'Hare in 1959, the following instances were notable: In 1977 the high was 91 with a low of 70, a hot day and year of the record warmest low. In 1975 the high was 83 with a low of 62, a warm day. In 1974 the low was a warm 64 degrees. In 1970 the high was a hot 86 with a low of 54, a 32 degree spread and hot day. In 1969 the high was a cool 54 with a low of 41, a cool day. In 1967 the high was a cool 57 with a low of 40, a cool day. In 1966 the high was 76 with a low of 43, a 33 degree spread. In 1964 the high was 89 with a low of 65, a hot day. In 1963 the high was 54 with a low of 35, a cool day. The low was colder than the record low. In 1962 the high was a warm 84 with a low of 51, a 33 degree spread. In 1961 the high was 60 with a low of 36, a cool day. The low was equal to the record low.

More recently, there was a small spread of seven degrees in 1998 (60/53). There were large spreads of 38 degrees in 1979 (75/37), 36 degrees in 1980 (82/46), 33 degrees in 1995 (78/45), 32 degrees in 2007 (87/55) and 31 degrees in 1993 (76/45).

On the cool side, in 2006 the high was 62 with the record low of 36. Three years earlier, in 2003, the high was 61 with a low of 39. The former record low was 37 in 1997. It was also 37 at O'Hare in 1979. Lows were 36 in 1961 and 35 in 1963. These were not official because O'Hare was not the official station of record for Chicago during these years. Other cool highs were 59 in 1986, 59 three years ago (in 2008) and 60 in 1998. The record coolest high of 44 occurred back in 1917. 26 of the last 32 lows (81%) were in the: 40s (11) and 50s (15). Four lows were in the cold 30s. Two lows were in the warmer 60s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 4:53 and sunrise is at 5:26. Sunset is at 20:14 and twilight ends at 20:47. There's a total of 14 hours, 48 minutes of daylight today and 15 hours, 54 minutes between twilights. We gained two minutes of daylight from yesterday. Tomorrow twilight begins at 4:52 and sunrise is at 5:25. The moon is waning gibbous. Illumination was 74% at midnight, will be 70% at noon and 65% at midnight tonight. Moonrise is at 0:11 this morning. Moonset is at 10:30 this morning. Moonrise is at 0:41 tomorrow morning. Moonlight time is 10 hours, 19 minutes which is 55 minutes longer than yesterday.

The warm part of Spring (Warm Spring) began on April 13. Warm Spring runs for 52 days, through June 3. High temperatures in this period are usually in the 50s, 60s and 70s. Warmer 80s and 90s occur infrequently. National Maritime Day is today. Memorial Day is in eight days. -Bernie-